System and method for controlling exhaust emissions and specific fuel consumption of an engine

Abstract

A method includes controlling an engine speed based on: intake manifold air temperature and/or intake manifold pressure one, or more, of the following data parameters: an engine load as a function of a fuel level, a fuel injecting timing, an intake oxygen concentration, a constituent concentration from the exhaust gas flow, an engine power, and an engine torque. The method also recirculates a portion of the exhaust gas flow to the combustion cylinders of the engine via a recirculation channel, as a function of intake manifold temperature and/or intake manifold pressure at which the engine is operated. An engine system, other methods, and a non-transitory computer readable medium encoded with a program, to enable a processor-based control unit to control aspects of the engine are also disclosed.

The invention claimed is: 
     
       1. A method comprising:
 controlling an engine speed based on:
 at least one of: intake manifold air temperature and intake manifold pressure; and 
 at least one data parameter of: an engine load as a function of an engine notch, a fuel injecting timing, an intake oxygen concentration, a constituent concentration in at least a portion of an exhaust gas flow, an engine power, and an engine torque; and 
 
 recirculating at least a portion of the exhaust gas flow to a plurality of combustion cylinder of the engine via a recirculation channel, as a function of at least one of the intake manifold temperature and intake manifold pressure at which the engine is operated. 
 
     
     
       2. The method of  claim 1 , further comprising selectively bypassing a turbine feeding at least a portion of the exhaust gas flow via an exhaust channel. 
     
     
       3. The method of  claim 1 , wherein a fuel level of the engine comprises a notch setting. 
     
     
       4. The method of  claim 1 , wherein the constituent concentration comprises at least one of: NOR, an exhaust oxygen content, and soot content. 
     
     
       5. The method of  claim 1 , wherein the at least one data parameter is disposed in at least one map, and further comprising:
 selecting a map from a plurality of maps based on at least one of: intake manifold air temperature, intake manifold air pressure, engine speed, engine load, ambient temperature, and altitude. 
 
     
     
       6. An engine system comprising:
 an engine comprising a plurality of combustion cylinders; 
 a turbine coupled to the engine, and configured to expand a first portion of an exhaust gas generated from the plurality of combustion cylinders; 
 a recirculation channel for recirculating a third portion of the exhaust gas to the plurality of combustion cylinders, as a function of at least one of intake manifold temperature and intake manifold pressure at which the engine operates; and 
 a controller configured to control engine speed based on:
 at least one of: intake manifold air temperature and intake manifold pressure; and 
 at least one data parameter of: an engine load as a function of an engine notch, a fuel injecting timing, an intake oxygen concentration, a constituent concentration in at least a portion of an exhaust gas flow, an engine power, and an engine torque. 
 
 
     
     
       7. The engine system of  claim 6 , further comprising an exhaust channel for feeding a second portion of the exhaust gas bypassing the turbine. 
     
     
       8. The engine system of  claim 6 , wherein a fuel level comprises a notch setting. 
     
     
       9. The engine system of  claim 6 , wherein the engine system has no aftertreatment system.